Aryloxy alkyl esters of cinnamic acid



Patented Oct. 28, 1941 Gerald H. Coleman and Bartholdt C. Hadler, M.id-7 land, Mich., assignors to The Dow Chemical Company, Midland, Mich., acorporation of I Michigan No Drawing;

8 Claims.

This invention concerns esters of certain aryloxy alcohols and cinnamicacid, and particularly relates tocinnamic acid esters having the generalformula wherein R represents an alkoxy substituent} R1 represents alower alkylene radical containing at Application January 23, 1941,Serial No. 375,623

least 2 carbon atoms,,i,' e. a bivalent aliphatic hydrocarbon radicalcontaining from 2 to 6 carbon atoms in which the free valences are borneby different carbon atoms; and R2 represents a member of the groupconsisting of the alkyl, alkenyl, and cycloalkyl radicals and hydrogen.All such esters are new compounds useful as plasticizing and modifyingagents for vinyl resins, e. g. polystyrene, and cellulose derivatives,e. g. ethyl cellulose, cellulose acetate, etc.

The cinnamic acid esters of the present classare conveniently preparedby esterifying an aryloxy alcohol in which the aryl group is substitutedby an alkoxy substituent such as 2-(3-methoxyphenoxy) -ethanol. Thereaction is carried out by heating the aryloxy alcohol withapproximately one molecular equivalent of cinnamic acid at a temperatureof about 60-130 C. until reaction is complete. If desired, a smallproportion of an esterification catalyst, e. g. 0.01-0.05 molecularequivalents of a strong acid such as sulfuric or benzene sulfonic acidmay be employed. Also if desired, a water-immiscible organic liquid suchas benzene or toluene may be added to the reaction mixture for thepurpose of promoting distillation and removal of water from the reactionmixture. Upon completion of the reaction, the mixture is treated withsufiicient alkali to neutralize any free acid contained therein, washedwith water, and the ester product is separated and purified byfractional distillation or crystallization.

The following examples are illustrative of the preparation of the estersof the present class but are not to be construed as limiting theinvention:

Example 1 A mixture of 182 grams (1 mol) of a mixture of isomeric(Z-methoxy-phenoxy) propanols (the reaction product of propylenechlorhydrin and 2-methoxy phenol), 163 grams (1.1 mols) of cinnamicacid, and 7.5 grams (0.05 mol) of benzene sulfonic acid was heated at92-130 C. for 18 hours in a flask fitted with a dropping funnel,condenser, and receiver arranged in such manher as to permitdistillation of water from the mixture during the heating, 300 cc. ofbenzene was addedslowly through the dropping funnel to facilitate thedistillation of water. Upon completion of the reaction the mixture wascooled,

dissolved in benzene, and washed successively with a dilute aqueoussodium bicarbonate solution and water. Benzene was removed bydistillation and the ester product was separated and purified byfractional distillation under vacuum, whereby there was obtained amixture of isomeric j (2-methoxy-phenoxy) propyl cinnamates; a paleyellow liquid which distills at approximately 200" C. under 1 millimeterpressure, has a specific gravity at O gg of 1.140

partially crystallizes on standing, and may be represented by theformula Example 2 A mixture of 208 grams (1 mol) of 2-(4-allyl- O of1.1310

, and a boiling point of about 235-240 C. under 1 millimeter pressure,and having the formula o-om O This application is a continuation-in-partof our co-pending application Serial No. 321,315,

filed February 28, 1940, which, in turn, is a continuation-in-part ofour application Serial No. 177,655, filed December 1, 1937.

We claim:

1. An aryloxy-alkyl ester of cinnamic acid having the general formulawherein R represents an alkoxy substituent and R2 represents a member ofthe group consisting of the alkyl, alkenyl, and cycloalkyl radicals andhydrogen.

3. An aryloxy-alkyl ester of cinnamic acid having the general formulawherein R represents an alkoxy substituent and.

R2 represents a member of the group consisting of the alkyl, alkenyl,and cycloalkyl radicals and hydrogen.

4. An aryloXy-alkyl ester of cinnamic acid having the general formulawherein R represents an alkoxy substituent.

5. An aryloxy-alkyl ester of cinnamic acid having the general formulawherein R represents an alkoxy substituent.

6. An aryloxy-alkyl ester of cinnamic acid having the general formulawherein R2 represents a member of the group consisting of the alkyl,alkenyl, and cycloalkyl radicals and hydrogen.

7. 2- (4-a1ly1-2-methoxy-phenoxy) -ethy1 namate.

8. (2-methoxy-phenoxy) -propyl cinnamate.

cin-

GERALD H. COLEMAN. BARTHOLDT C. HADLER.

